Bladed rotor and the like for axial flow fluid machines



Oct. 31, 1961 E. A. STALKER 3,006,605

BLADED ROTOR AND THE LIKE FOR AXIAL FLOW FLUID MACHINES Filed June 4,1958 IN V EN TOR.

United States atent ()fitice 3,006,605 BLADED ROTOR AND THE LIKE FORAXIAL FLOW FLUID IJACHINES Edward A. Stalker, 406 N. Farragut St., BayCity, Mich. Filed June 4, 1958, Ser. No. 739,332 6 Claims. (Cl. 253-77)My invention relates to bladed rotors and the like for axial flowcompressors, turbines and the like.

An object of my invention is to provide an economical and light weightrotor particularly adapted to sheet metal construction.

Another object is to provide a rotor wherein the joints are readilyinspectable.

Still another object is to provide a bladed structure wherein the bladesare supported on a single disk by a simple connection.

Other objects will appear from the specification, appended claims, andaccompanying drawings.

The above objects are accomplished by the means illustrated in theaccompany drawings in which FIG. 1 is an axial view of a fragment of arotor according to the subject invention;

FIG. 2 is a fragmentary section on line 22 in FIG. 1;

FIG. 3 is a fragmentary section on line 3-3 in FIG. 2;

FIG. 4 is a section on line 44 in FIG. 2;

FIG. 5 is a fragmentary section on line 5-5 in FIG. 2;

FIG. 6 shows a fragment of the inner end of a hollow blade with the legsspread apart before engagement with the disk of the rotor; and

FIG. 7 shows a fragment of the inner end of a blade whose legs areintegral with the blade surface and spread apart before engagement withrotor disks.

In this invention the blade may be solid or composite with a stem bondedinteriorly of the blade shell. Such a composite blade will usually behollow. The stem extends radially inward through the rim means andengages the rim mechanically. It may also be bonded to the disk by fusedmetal, braze metal for instance.

Referring now to the drawings the rotor is indicated generally by 10. Itcomprises the blade 12 and the hub means 14.

The hub means 14 comprises the hollow rim means 16 and the rotor bladecentral support disk 29 positioned between the leading and trailingedges of the blades.

The blades are spaced peripherally, FIGS. 1 and 3, and each comprises ablade shell and a root portion integral therewith preferably of athicker wall than the shell. The root portion fairs into the shell by agenerous fillet, and a stem 22 fixed internally of the blade andextending radially inward through the rim of the rim means to a junctionwith the rotor disk for support thereby.

The stem has the two legs 23 and 24 which have the tenons 30 and 32,FIGS. 1, 2 and 5, which pass through openings 34 in the disk. These areperipherally spaced about the support disk. The tenons fit closely tothe sides of the openings and to each other in side by side relation.

Each leg preferably bears on the disk whichis re ceived between them andis preferably bonded thereto by fused metal preferably braze metal. Thestem and disk form a simple light structure capable of supporting theblade against the forces arising from its rotation in use. The disk mayalso be reinforced by a ring 46 bonded to the disk.

The disk preferably has peripherally spaced notches in its peripheryinto each of which the inner end of the root portion of a blade fits andis preferably bonded to give additional side support to the blade means.

The rim means comprises the rim segments 42 between blades at their rootportions (see FIGS. 1 and 3), the rim side rings 44 and 46, and theangles 47 and 48 fixed to the rim segments and preferably bonded to theroot portions of the blades. Preferably the rings have flanged openings50 for stiffening the rings and for acess to the legs and joints of eachstem with the hollow rim means which is closed to radial view by theperipheral portions of the disk.

The rim means extend from front to rear of the rotor and from blade toblade to sustain variations in fluid pressure. The rim means is securedto the disk for support thereby.

The disk is metal to provide rigidity and homogeneous strengthproperties in all radial directions so that it can support the bladesbearing against the radially outward sides of the disk holes for supportagainst the centrifugal forces. The disk is prepierced with generallyrectangular holes directed radially, that is having their majordimension along the radius. The tenons would have a cross section at thedisk conforming to the shape of the holes. This rectangular crosssection is necessary to provide adequate shear strength in the tenon.Thus adequate strength is provided while retaining the low cost featureof a generally flat root portion of the blade including the legs andtenons.

The stem is first formed with the legs spread apart as shown in FIG. 6providing a gap 54 just large enough for the stem to straddle the disk.The legs are then pressed toward each other and through the hole in thedisk.

The blades may have the legs integral with a blade surface includingthat of a solid blade with tenons formed in the legs as shown in FIG. 7.The tenons are to engage the disk in the same manner as of FIGS. 2 and5.

The disk may be attached to a shaft means 57 by bolts 58 spacedperipherally about the disk, for instance. The rotor rotates with theshaft about the axis of symmetry of the rotor or disk.

It will now be clear that I have provided a light weight and economicalrotor. The blades are simple to make since they require no costly andheavy machined rotor rims. Furthermore the connections of the blades tothe disk are easily inspected.

While I have illustrated specific forms of the invention, it is to beunderstood that variations may be made therein and that I intend toclaim my invention broadly as indicated by the appended claims.

I claim:

1. In combination in an axial flow rotor adapted to change the pressureof a fluid, a metal sheet defining a blade support disk having an axisof rotation and having a plurality of prepierced peripherally spacedholes therethrough, a plurality of blades peripherally spaced about saiddisk with the spans thereof extending radially outward from said diskrelative to said axis, each said blade having an integral leg positionedalong an axially facing side of said disk with a tenon thereof in a saidhole in radially outward bearing relation on said disk for theengagement thereof by said tenons to support the blade by said diskagainst centrifugal force in operation of said rotor, each said tenonbeing of generally flat form extending in the general radial directiondefininga generally rectangular cross section thereof at said disk toprovide sufiicient radial extent of said tenon to support said bladeagainst centrifugal force in use, said prepierced holes having agenerally rectangular cross section conforming closely to said crosssection of said tenon for the receipt thereof within said holes in closefitting relation, said tenons being brazed to said disk at the sides ofsaid holes thereof and rim means secured to said disk, said rim meansencircling said disk with the rim thereof extending from 3 front to rearof said blades and from blade to blade to sustain variations in saidfluid pressure.

2. In combination in an axial flow rotor, a metal sheet defining a bladesupport disk having an axis of rotation and having a plurality ofprepierced peripherally spaced holes therethrough, a plurality of axialflow blades having root portions at their radially inner ends and beingperipherally spaced about said disk with the spans thereof extendingradially outward from said disk relative to said axis, each said bladehaving legs fixed in said blade and straddling said disk, said legshaving tenons side by side in a said hole in bearing relation on saiddisk for the engagement thereof by said tenons to support said blade bysaid disk against centrifugal force, said ten'ons being bonded to eachother and to said disk, each said tenon being of generally flat formextending in the general radial direction defining a generallyrectangular cross section thereof at said disk to provide sufficientradial extent thereof to support said blade against centrifugal force inuse, said prepierced holes having a generally rectangular cnoss sectionconforming closely to said cross section of said tenon for the receiptthereof within said holes in close fitting relation, and rim means atthe root portions of said blades secured to said disk, said rim meansencircling said disk with the rim thereof extending from front to rearof said blades and from blade to blade to sustain variations in saidfluid pressure.

3. In combination in an axial flow rotor adapted to change the pressureof a fluid, a metal sheet defining a blade support disk having an axisof rotation and having a plurality of prepierced peripherally spacedholes, a plurality of composite blades peripherally spaced about saiddisk with the spans thereof extending radially outward from said diskrelative to said axis, each said blade having a hollow blade shell and astem therewithin bonded to the internal surfaces thereof, each said stemhaving integral legs straddling said disk, said legs having integraltenons side by side in a said hole in bearing relation on said disk forthe engagement thereof by said tenons to support said blade againstcentrifugal force, each said tenon being of generally flat formextending in the general radial direction defining a generallyrectangular cross section thereof at said disk to provide suflicientradial extent thereof to support said blade against centrifugal force inuse, said prepierced holes having a generally rectangular cross sectionconforming closely to said cross section of said tenon for the receiptthereof within said holes in close fitting relation, and rim means atthe root portions of said blades secured to said disk, said rim meansencircling said disk with the rim thereof extending from front to rearof said blades and from blade to blade 'to sustain variations in saidfluid pressure.

4. In combination in an axial flow rotor, a rigid sheet of materialdefining a blade support disk having an axis of rotation and having aplurality of prepierced peripherally spaced holes, a plurality of axialflow blades having root portions at their radially inner ends and beingperipherally spaced about said disk with the spans thereof extendingradially outward from said disk relative to said axis, each said bladehaving legs straddling said disk, said legs having integral tenons sideby side in a said hole in bearing relation on said disk to support saidblade by said disk, said side by side tenons being brazed to each otherto form a brazed joint, and rim means at the root portions of saidblades secured to said disk, said rim means encircling said disk withthe rim thereof extending from 4 front to rear of said blades and fromblade to blade to sustain variations in said fluid pressure, said rimmeans encompassing said root portions and excluding said portions fromradial view, said rim means having openings in the sides thereofopposite said tenons to provide for the inspection of said brazedjoints.

5. In combination in a bladed rotor for compressors, turbines and thelike, a sheet of rigid material defining a central disk having aplurality of peripherally spaced holes and a plurality of bladesperipherally spaced about said disk and having their spans extendingradially therefrom, each said blade having integral legs straddling saiddisk, each said leg having integral tenons overlapping along thechordwise direction and brazed to each other along said sides andextending in the general radial direction in a said hole in bearingrelation on said disk for the engagement thereof by said tenons, eachsaid tenon being of generally flat form extending in the general radialdirection defining a generally rectangular cross section thereof at saiddisk to provide sufficient radial extent thereof to support said bladeagainst centrifugal force in use, said prepierced holes having agenerally rectangular cross section conforming closely to said crosssection of said ten'on for the receipt thereof within said holes inclose fitting relation.

6. In combination in a bladed structure for compressors, turbines andthe like, a sheet of rigid material defining a central disk, a rim meanshaving blade openings and encircling said disk and fixed thereto, aplurality of blades peripherally spaced about said disk and having theirspans extending radially inward through said openings of said rim meansalong said disk, each said blade having a leg having a tenon integraltherewith positioned in a hole in radially outward bearing relation onsaid disk for the engagement thereof by said tenons to sustain the bladeagainst centrifugal force, each said tenon being of generally flat formextending in the general radial direction defining a generallyrectangular cross section thereof at said disk to provide suflicientradial extent of said tenon to support said blade against centrifugalforce in use, said prepierced holes having a generally rectangular crosssection conforming closely to said cross section of said tenon for thereceipt thereof Within said holes in close fitting relation, each saidtenon being bonded to said disk at the sides of said hole therein, saidblades bearing on said rim means at said holes for support againstforces transverse to said span and being bonded to said rim means.

References Cited in the file of this patent UNITED STATES PATENTS819,106 Wilkinson May 1, 1906 913,273 Emden Feb. 23, 1909 1,775,353Marinsky Sept. 9, 1930 2,082,739 MacWilliams June 1, 1937 2,457,325Sidell Dec. 28, 1948 2,626,741 Osborne Jan. 27, 1953 2,678,537 StalkerMay 18, 1954 2,692,563 Kovacs Oct. 26, 1954 2,801,071 Thorp July 30,1957 FOREIGN PATENTS 514,798 Canada July 19, 1955 701,263 Great BritainDec. 23, 1953 740,909 Great Britain of 1955 840,183 Germany May 29, 1952881,279 Germany June 29, 1953

